Electrical-circuit protective apparatus.



110.800,824. PATENTED 00T.3,1905. 0. A. RoLTB.

ELECTRICAL 0TR0U1'T PROTECTIVE APPARATUS.

APPLICATION FILED PEB.1'3. 1903.

"UNITED sTAfrns CHARLES A. ROLFE, OF ADRIAN,

PATENT OFFICE.

MICHIGAN, ASSIGNOR, BY MESNE ASSIGNMENTS, TO ROLFE ELE )TRIC CO., OFROCHESER, NEIV YORK, A CORPORATION OF NEY YORK.

Speccation of Letters Patent,

Patented Oct. 3, 1905.

Application iiled February I3, 1903. Serial No. 143,225.

T0 all whomJ it Trl/fly concern.-

Be it known 'that I, CHARLES A. RoLFn, a citizen of the UnitedStates,residing at Adrian, in the county of Lenawee and State ofMichigan, have invented a certain new and useful Improvement inElectrical-Circuit Protective Apparatus, of which the following is afull, clear, concise, and exact description, reference being had to theaccompanying drawings, forming a part of this speciiication.

My invention relates'to protective apparatus for protecting' electricalcircuits from the harmful effects of unduly-strong currents andexcessively-high potentials.

Prominent objects of the invention are to provide a simple, practical,and durable form of protective apparatus, to secure cheapness andsimplicity of construction, and to attain a high degree of efliciencyand operation.

In the present application I show my invention embodied in abank-protective apparatusthat is, a series oi" protective devices for aplurality of circuits all assembled together4 lan arrangement of specialuse and advantage in central exchanges, for example, where a largenumber of circuits converge to a single building.

In the accompanying drawings, Figure 1 is a side elevation of a sectionof a bank-protective apparatus embodying my invention. Fig. 2 is atransverse section of the same in its normal condition, and Fig. 3 is asimilar section of the apparatus in an operated condition.

The apparatus shown in the drawings for carrying out the inventioncomprises a base or plate 1, conveniently arranged in upright positionand desirably made of metal, although it can be made of insulatingmaterial. This forms the central body portion of the structure, and onopposite sides are arranged series of protective devices, one series oneach side. The different devices in the two series are arranged oppositeone another, and it is intended that oppositely-located protectivedevices shall be for the same circuit, one being included on each sideof the circuit. Each protective device consists of a pair of springs 2 3and a separable structure 4, commonly called a "cartridgej7 mounted uponand engaging the springs 2 and 3. The springs 2 and 3 of each pair tendto separate from one another, but are held in restraint by the cartridge4. The latter consists of a body 5, desirably made of insulatingmaterial and having its ends provided with caps 6 and 7, whereoil thecap 6 engages the spring' 2. The cap 7 is constructed with a pair ofears 8 8, and between these is arranged a bell-crank lever 9, one ofwhose arms projects down below the cartridge and the other of whichprojects out beyond the end of the same. A spring 10 is secured to thebody 5 and arranged to press against the outer end of the bell-crank 9.The bell-crank 9 is held normally in position by solder, which isintroduced between the ears 8 8. The body is provided with a bore oraperture near one end, and in this is located a high-resistance graphitestick 11. A contact 12 is secured to the cap 4 and extended over to thegraphite stick 11, with whose lower end it makes contact. The upper endof the stick 11 is in contact with the upper wall of the cap 7. One olthe springs 2 is provided with a pin or spindle 13. The connection isdesirably made of set-nuts 14 14, by which adjustment can be sccured.The pin 13 extends from the spring 2, to which it is attached, throughthe plate 1 nearly to the opposite spring 2, as shown in Fig. 2. Outsideof each spring' 3 is a pair of springs or contacts 15 and 16, the spring16 having its end bent toward the spring' 15 and the latter having itsupper end bent toward the spring 3. The spring 3 is provided with apiece of insulation 17 opposite the upper end of the spring 15.

The springs 2 2, 3 3, 15 15, and 16 16 are all supported and secured tothe plate 1 by bolts 18 and 19, extending' through the plate 1.Insulation-strips 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, and 30 andmetal nuts or bushings 31, 32, 33, and 34 are arranged upon the bolt 18,and this bolt is provided with insulating'- sleeves 35, 36, and 37.Insulating-strips 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, and 50and metal nuts or bushings 5l, 52, and 53 are arranged upon the bolt 19,and this bolt is provided with insulating-sleeves 54, 55, and 56.Contact or connecting strips 57 and 58 are provided, the strip 5( beingmounted on the bolt 19 between the .insulation 41 and the nut 51, andthe strip 58 being mounted on both the bolts 18 and 19 and between thenut 34 and insulation 26 on the Aformer and nut 53 and insulation 45 and46 on the latter.

The left-hand spring 2 is provided with a lower extension 59, adapted toform a con- IOO IOS

nector or terminal, andthe right-hand spring 3 is provided with a smallextension 60. These terminals or connecting-strips are intended for theconnecting-wires oli the circuit, the terlninals 57 and 59 being for theline and the terminals 53 and 60 for the switchboard or instrument.

Metal strips 61 and 62 are arranged on opposite sides of thesupporting-plate 1 and extend upwardly along'side olI the same. Theirlower ends are mounted upon the bolts 13 and 19, the lower portion ofthe strip 61 being located between the nuts 32 and insulation 2st andbetween the nut 52 and insulation 43 and thc lower portion et the strip62 being' located between the insulation 25 and nut 33 and insulation 44and nut A ground-plate 63 is mounted upon the upper end of thesupporting-plate 1, and on opposite sides ot' this ground-plate 63 arelightning-arrester carbons 64C 6a and 65 65, the carbons 6ft, 64k beingground-carbons and 65 65 line-carbons, one pair 64: 65 beingl located oneach side ot' the ground-strip 63. Between the pairs 64 and 65 arelocated insulation-strips 66 66, which may be of any suitablematerial-eas, for example, mica or the like. The metal line-strips 61and 62 lit in grooves in the carbons 65 65 and press inwardly againstthe same, thereby holdingl the carbons in place.

Then the line-wires are connected with the terminals 57 and 59 and theinstrument or switchboard wires with the terminals 58 and 60, circuit ismade through the two sides ot' the device as follows: from line toterminal 57, nut 51, bolt 19, nut 53, right-hand spring 2, cartridgesupported thereby, spring 3 in part supporting said cartridge, andterminal to switchboard; thence back to terminal 58, to nut 34, bolt 13,nut 31, left-hand spring 3, cartridge in part supported thereby, spring2 in part supportingsaid cartridge, and down the same to terminal 59,and thence to line. The lightning-arrester strips 61 and 62 b-y being incontact with the nuts 32 and 53, respectively, are connected with theopposite sides of the line, thereby putting the lightningarrestercarbons 65 in connection with the opposite sides ot' the line and makingthem linecarbons. rlheground-strip 63 is understood to be connected toground in any suitable or desired way, a simple method being to putit inelectrical contact with the plate 1 and connect the latter to ground.

l/Vhen the circuit is being traversed by a normal current, the apparatusis in the condition illustrated in Fig. 2. Vhen, however, anundLily-strong` current traverses the circuit, one or both of thegraphite sticks 11 in the cartridges is orare heated to an extent tomelt or soften the solder holding the levers 9 9 in position. lf thesolder of but one ot' the cartridgesis softened or melted, the lever ofthat cartridge is released, thereby permitting the corresponding` spring2 to swing or spring outwardly to the position illustrated in Fig. 3.The spring in moving outwardly passes and separates lrom the end ot thelever 9, thereby breaking or opening' the circuit at that point. .llIthe lett-hand cartridge, Figs. 2 and 3, is the one which has operated,the letthand spring 2 will strike against the end ot the pin 13, therebymaking electrical connection with said pin and short-cireuiting theline, as well as opening the circuit to protect the instrument. llC theright-hand cartridge is the one which is operated, the right-hand spring2 will swing or springinwardly, thereby pushing the pin 13 against thelett-hand spring with the same result. It' both cartridges operate, thetwo springs 2 2 move toward one another and the pin 13 is brought intocontact with the left-hand spring 2, as shown in Fig. 3. Each ol thesprings 3 l) in operating brings the associated contact-spring 15against the corresponding contact-strip 16, thereby closing a localalarm-circuit which is understood to be suitably connected with thesecontacts. The connections are such that the alarm will be given whetherone or both sets o1 contacts are connected. After either cartridge hasoperated and its spring 3 released the small spring 10 of that cartridgewill automatically actuate the lever 9 to swing the same back intonormal or original position. lVithin a short time after such action thesolder will become again hard andthe lever 9 again held in its originalposition. 1t will thus be seen that in the operation of the device,whether either one or both of the cartridges operate, the circuit willbe opened at the instrument to protect the same and the line will heautomatically short-ci rcuited, and at the same time a localalarm-circuit will be closed to give any suitable alarm. After suchoperation either or both ot' the cartridges are automatically restoredto operative condition. Thus when the alarm has been attended and thetrouble on the circuit located and removed the device can be reset bysimply engaging one or both of the springs 3 3 with its cartridge orcartridges.

1n certain other applications lor patents filed by me and new pending'in the Patent Otlice I have disclosed certain o't' the `features setforth herein, and so do not claim them alone in this application.

that I claim as my invention is- 1. In apparatus of the class specified,the combination of oppositely-disposed protective devices, each adaptedto operate upon the passage in the circuit of an unduly-strong current,and means for short-circuiting the circuit upon the operation of one ofsaid devices, substantially as described.

2. In apparatus of the class specified, the combination otoppositely-disposed protective devices, each adapted to operate upon thepassage in the circuit of an unduly-strong current, and means forshort-circuiting the circuit upon the operation of either or both ofsaid devices, substantially as described.

3. In apparatus of the class specified, the combination ofoppositely-disposed sets of springs, excesssoperated devices for holdingsaid springs in restraint under normal condition and for releasing thesame upon the passage in the circuit of an unduly-strong current, andmeans for electrically connecting a spring in one set with a spring inthe other set, upon the operation of one of said excessoperated devices,substantially as described.

1. In apparatus of the class specified, the combination ofoppositely-disp'osed sets of springs, excess-operated devices forholding' said strips in restraint under normal condition and forreleasing the same upon the passage in the circuit of an unduly-strongcurrent, and means for electrically connecting' a spring in one set withaspring in the other set, upon the operation of either of saidexcessoperated devices, substantially as described.

5. In apparatus of the class specified, the combination ofoppositely-disposed sets of springs, excess-operated devices for holdingsaid strips in restraint under normal condition and for releasing thesame upon the passage in the circuit of an unduly-strong current, andmeans for electrically connecting a spring in one set with a spring inthe other set, upon the operation of either or both of saidexcess-operated devices, substantially as described.

6. In apparatus of the class specified, the combination withoppositely-disposed sets of springs, of excess-operated devicessupported by said springs and holding the same in restraint, theadjacent springs being adapted to spring toward one another, and a pincarried by one of said springs and projecting toward thc other,substantially as described.

7. In apparatus of the class specified, the combination ofoppositely-disposed sets of spring-strips whereof the inner strips tendto spring toward one another and the outer ones away from one another,heat-cartridges holding said spring-strips in restraint, each of saidcartridges consisting of a heat-concentrating device and a movablepartheld in position by softenable or fusible material, and means forrestoring said movable part to normal condition, the movable parts ofsaid cartridges being engaged by said spring-strips, and a pin carriedby one of the inner spring-strips and projecting toward the other,substantially as described.

8. In apparatus of the class specified, the combination of asupporting-plate 1, sets of spring-strips 2, 3 supported by said plate1, the springs 2, 2, being adapted to spring toward the plate and thesprings 3, 3, away from the same, heat-cartridges, one carried by eachset of spring-strips 2, 3, each cartridge comprising a graphite stick, amovable part held in normal position by solder and aspring acting uponsaid movable part to restore the same to normal condition while thesolder is still soft, and a pin 13 carried by one of the spring-strips 2and projecting' toward the other, substantially as described.

9. In apparatus of the class specified, the combination of a pair ofoppositely-disposed protective devices, each adapted to open the circuitat the instrument upon operation and means for affording a connectionbetween said devices so as to short-circuit the line upon the operationof either device.

10. In apparatus of the class specified, the combination of a pair ofoppositely-disposed protective devices, each adapted 'to open thecircuit at the instrument, upon operation, and means for affording' aconnection between said devices so as to shortecircuit the line upon theoperation of either or both devices.

11. An electrical controller, comprising thermally-operable means forshort-circuiting the circuit, and having provisions for automaticallyrestoring itselfl to operative condition preparatory for anotheroperation.

12. An electrical-circuit protector. comprising thermally-operable meansfor shortcircuiting the circuit on the passage of an unduly-strongcurrent, and having provisions for automatically restoring itself tooperative condition.

13. An electricalcircuit protector comprising thermally-operable meansfor shortcircuiting the circuit on the passage of an unduly-strongcurrent, and having provisions for automatically resetting itself foranother operation and resecuring itself in reset condition.

14. An electrical-circuit controller, comprising means forshort-circuiting the circuit on the passage of an unduly-strong current,and having provisions for automatically re- 'soldering itselfpreparatory for another operation.

15. An electricalcircuit protector comprising a pair of solder-jointprotective devices, each having provisions whereby it is automaticallyresoldered in operative condition, said protector having means wherebyon the operation of either of said protective devices the circuit isautomatically short-circuited.

16. In electrical protective apparatus, the combination of a pair ofoppositely-disposed solder-joint protective devices, each havingprovisions whereby after operation it is automatically resolderedpreparatory for another operation, and means whereby the operation ofeither of said protective devices short-circuits the circuit.

17. An electrical protector comprising a pair of oppositely-disposedprotective devices, each consisting of a heat-cartridge andsupporting-strips therefor, one of which has a spring action, saidheat-cartridge having a solder-joint normally holding said spring-stripIOO IIO

IZO

in restraint and having provisions for automatically resoldering itselfin operative condition.

18. An electricalcircuit protector, comprising a pair of protectivedevices, each consisting of a solder-joint heat-cartridge and supportingmembers therefor, one of which is a spring held in restraint by saidcartridge, and ametal bar carried by one of the supporting members ofone of the protective devices, and adapted to make connection with oneof the supporting members of the other protective devi'ce on theoperation of one of said devices.

19. An electricalcircuit protector, comprisingl a pair of protectivedevices, each consisting of a solder-joint heat-cartridge havingprovisions for automatically resoldering itself in operative condition,and supporting members for said cartridge, one of which is a spring, andmeans for short-circuiting the circuit on the operation of either one ofsaid cartridges.

20. In a device of the class specified, the combination of a pair ofprotective devices, and means for connecting the same so as toshort-circuit the line upon the operation of either.

21. In a device of the class specilied, the combination of a pair ofprotective devices, and means for connecting the same so as toshort-circuit the line upon the operation of either or both.

22. In a device of the class specified, the combination of a pair ofprotective devices, each of said devices being` adapted to open thecircuit, and means for affording connection between said devices so asto short-circuit the line upon the operation of either device.

23. In a device of the class specilied, the combination of a pair ofprotective devices, each of said devices being1 adapted to open thecircuit', and means for affording connection between said devices so asvto short-circuit the line upon the operation of either or both devices.

In witness whereof I hereunto subscribe my name this 22d day of January,A. I). 1903.

CHARLES A. ROLFE.

Titnessesz A. MILLER BELFIELD, I. C. LEE.

